Chair assembled from blow-molded parts without tool

ABSTRACT

A chair includes a lower block and an upper block. The lower block is put on the ground. The upper block includes a hollow seat and a hollow backrest. The hollow seat is installed on the lower block. The hollow backrest is installed on the hollow seat. The hollow seat is made via blow molding. The hollow backrest is made via blow molding.

CROSS-REFERENCE

[0001] The present application is a continuation-in-part application ofU.S. patent application Ser. No. 10/425373.

FIELD OF INVENTION

[0002] The present invention relates to a chair assembled fromblow-molded parts without any tool.

BACKGROUND OF INVENTION

[0003] A typical chair includes a lower block and an upper block mountedon the lower block. The lower block includes a base for installment onthe ground, a telescopic post mounted on the base, a control deviceconnected with the telescopic post for control over the extending andshrinking of the telescopic post. The upper block includes a seatmounted on the control device, a backrest mounted on the seat and twoarmrests mounted on the seat. The seat, the backrest and the armrestsare separately molded and then assembled. This practice however requiresa lot of labor and time and therefore entails a high cost.

[0004] U.S. patent application Ser. No. 10/425373 discloses a chairincluding a lower block put on the ground and an upper block installedon the lower block. The upper block includes a hollow seat and a hollowbackrest installed on the hollow seat. The hollow seat and the hollowbackrest are both made via injection molding. The hollow seat and thehollow armrests are made of adequate sizes. Yet, only a little materialis required since they are hollow. Adequate sizes provide sufficientstrengths. A little material entails a low cost in fabrication. A littlematerial results in a small weight that entails a low cost intransportation. Take the hollow seat for example, the injection moldingrequires a mold and an insert. The mold and the insert are both made ofat least one part. The insert is put in the mold. Molten plasticmaterial is injected in a space defined via the mold and the insert.After being cured, the upper block is removed from the mold, and theinsert is removed from the hollow seat. It could be very difficult toremove the insert from the hollow seat.

[0005] The present invention is therefore intended to obviate or atleast alleviate the problems encountered in prior art.

SUMMARY OF INVENTION

[0006] It is an objective of the present invention to provide a chairthat can easily be manufactured.

[0007] It is another objective of the present invention to provide achair that can be manufactured at a low cost.

[0008] It is another objective of the present invention to provide achair that is strong in structure and light in weight.

[0009] According to the present invention, a chair includes a lowerblock and an upper block. The lower block is put on the ground. Theupper block includes a hollow seat and a hollow backrest. The hollowseat is installed on the lower block. The hollow backrest is installedon the hollow seat.

[0010] The hollow seat and the hollow backrest may both be made via blowmolding.

[0011] Other objects, advantages, and novel features of the inventionwill become more apparent from the following detailed description whentaken in conjunction with the attached drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0012] The present invention will be described through detailedillustration of embodiments referring to the drawings.

[0013]FIG. 1 is an exploded view of a chair according to a firstembodiment the present invention.

[0014]FIG. 2 is a perspective view of the chair shown in FIG. 1.

[0015]FIG. 3 is a cross-sectional view of the chair shown in FIG. 2.

[0016]FIG. 4 is a perspective view of a chair according to a secondembodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0017] Referring to FIGS. 1˜3, according to a first embodiment of thepresent invention, a chair 10 includes a lower block and an upper blockmounted on the lower block.

[0018] The lower block includes a base 12 for installment on the ground,a telescopic post 14 mounted on the base 12, a control device 16connected with the telescopic post for control over the extending andshrinking of the telescopic post 14. The lower block is conventional andhence will not further be described in detail.

[0019] The upper block includes a hollow seat 18 mounted on the controldevice 16 and a hollow backrest 20 mounted on the hollow seat 18. Thehollow seat 18 and the hollow backrest 20 are both made via blowmolding.

[0020] The hollow seat 18 includes an opening 22. The opening 22 isdefined in the hollow seat 18 during blow molding of the hollow seat 18.The hollow seat 18 includes two apertures 24 drilled or punched therein.

[0021] The hollow backrest 20 includes a reduced neck 26 put in theopening 22 so as to connect the hollow backrest 20 with the hollow seat18. The neck 26 includes two apertures 28 (only one is shown) drilled orpunched therein. A bolt 30 is driven into the apertures 24 and 28 so asto secure the hollow backrest 20 to the hollow seat 18. The upper blockis assembled from the hollow seat 18 and the hollow backrest 20 withoutany tool.

[0022]FIG. 4 shows a chair according to a second embodiment of thepresent invention. The second embodiment is identical to the firstembodiment except for including two armrests 32 mounted on the hollowseat 18. The hollow seat 18 includes two cavities 34 defined in the topand four apertures 36 defined in the top. Two of the apertures 36 arelocated within each of the cavities 34. Each of the armrests 32 includestwo inserts 38 extending from the bottom. The bottom of each of thearmrests 32 is put in one of the recesses 34, thus attaching thearmrests 32 to the hollow seat 18. The inserts 38 of each of thearmrests 32 are inserted in the apertures 36 located within one of therecesses 34, thus securing the armrests 32 to the hollow seat 18. Theupper block is assembled from the hollow seat 18, the hollow backrest 20and the armrests 32 without any tool.

[0023] The present invention has been described via detailedillustration of three embodiments. Those skilled in the art can derivevariations from the embodiments without departing from the scope of thepresent invention. Therefore, the embodiments shall not limit the scopeof the present invention defined in the claims.

1. A chair including a lower block put on the ground and an upper blockinstalled on the lower block, the upper block including a hollow seatand a hollow backrest installed on the hollow seat.
 2. The chairaccording to claim 1 wherein the hollow seat is made via blow molding.3. The chair according to claim 1 wherein the hollow backrest is madevia blow molding.
 4. The chair according to claim 1 wherein the hollowseat includes an opening defined therein, and the hollow backrestincludes a reduced neck inserted in the opening.
 5. The chair accordingto claim 4 wherein the opening is defined therein while molding thehollow seat.
 6. The chair according to claim 5 further including afastener, wherein the hollow seat includes an aperture defined therein,and the neck includes an aperture defined therein, and the fastener isdriven into the apertures.
 7. The chair according to claim 1 wherein theupper block includes two armrests mounted on the hollow seat.
 8. Thechair according to claim 7 wherein the hollow seat includes twoapertures defined therein, and each of the armrests includes an insertextending from a lower end into one of the apertures.
 9. The chairaccording to claim 7 wherein the hollow seat includes two cavitiesdefined therein, and each of the armrests includes a lower end put inone of the cavities.
 10. The chair according to claim 9 wherein thehollow seat includes two apertures defined therein each located withinone of the cavities, and each of the armrests includes an insertextending from the lower end into the aperture located within one of therecesses.
 11. The chair according to claim 1 wherein the lower blockincludes a base for installment on the ground and a post mounted on thebase.
 12. The chair according to claim 11 wherein the post istelescopic.
 13. The chair according to claim 12 wherein the lower blockincludes a control device connected with the telescopic post for controlover the extending and shrinking of the telescopic post.